An inductor is an element of a circuit used for sending and receiving high frequency signals. It is often shaped similar to a coil. An inductor can be implemented in a metal pattern with a spiral shape in a fabrication process of a semiconductor. Spiral-shaped inductors are often used in RF devices and analog devices. These devices are very important to the growing wireless communication market, and the characteristics thereof are represented by a Quality factor (Q).
Related art semiconductor devices that include an inductor generally have an inductor layer on an RF device circuit unit layer. The RF device circuit unit layer is formed, and the inductor layer is formed on the RF device circuit unit layer.
Since a metal film used to form the inductor layer is typically very thick, the process has many disadvantages. Also, the process is complicated by the fact that a transistor and a metal wiring are present on the substrate before the inductor layer is formed. When errors occur in the process of fabricating the inductor layer, the device formed below it on the substrate is rendered useless.
Thus, there exists a need in the art for an improved semiconductor device and fabrication process thereof.